User blog comment:Andr33wking/3 Faulty Things on Brick Bronze/@comment-30155146-20171225225531

http://brickbronze.wikia.com/wiki/Pok%C3%A9mon_Brick_Bronze_Wikia:Rarity_Scale

You can retest Deino's rate if you want, but I think you might have to do 1000+ encounters to get a more accurate scale than what we have now.